chore(code): move load options parsing to crates/eficore

crates/eficore/src/env.rs

@@ -0,0 +1,77 @@
+use alloc::string::{String, ToString};
+use alloc::vec::Vec;
+use anyhow::{Context, Result, bail};
+use uefi::proto::loaded_image::{LoadOptionsError, LoadedImage};
+
+/// Loads the command-line arguments passed to the current image.
+pub fn args() -> Result<Vec<String>> {
+    // Acquire the current image handle.
+    let handle = uefi::boot::image_handle();
+
+    // Open the LoadedImage protocol for the current image.
+    let loaded_image = uefi::boot::open_protocol_exclusive::<LoadedImage>(handle)
+        .context("unable to open loaded image protocol for current image")?;
+
+    // Load the command-line argument string.
+    let options = match loaded_image.load_options_as_cstr16() {
+        // Load options were passed. We will return them for processing.
+        Ok(options) => options,
+
+        // No load options were passed. We will return an empty vector.
+        Err(LoadOptionsError::NotSet) => {
+            return Ok(Vec::new());
+        }
+
+        Err(LoadOptionsError::NotAligned) => {
+            bail!("load options are not properly aligned");
+        }
+
+        Err(LoadOptionsError::InvalidString(error)) => {
+            bail!("load options are not a valid string: {}", error);
+        }
+    };
+
+    // Convert the options to a string.
+    let options = options.to_string();
+
+    // Use shlex to parse the options.
+    // If shlex fails, we will perform a simple whitespace split.
+    let mut args = shlex::split(&options).unwrap_or_else(|| {
+        options
+            .split_ascii_whitespace()
+            .map(|string| string.to_string())
+            .collect::<Vec<_>>()
+    });
+
+    // Correct firmware that may add invalid arguments at the start.
+    // Witnessed this on a Dell Precision 5690 when direct booting.
+    loop {
+        // Grab the first argument or break.
+        let Some(arg) = args.first() else {
+            break;
+        };
+
+        // Check if the argument is a valid character.
+        // If it is not, remove it and continue.
+        let Some(first_character) = arg.chars().next() else {
+            break;
+        };
+
+        // If the character is not a printable character or a backtick, remove it and continue.
+        if first_character < 0x1f as char || first_character == '`' {
+            args.remove(0);
+            continue;
+        }
+        break;
+    }
+
+    // If there is a first argument, check if it is not an option.
+    // If it is not, we will assume it is the path to the executable and remove it.
+    if let Some(arg) = args.first()
+        && !arg.starts_with('-')
+    {
+        args.remove(0);
+    }
+
+    Ok(args)
+}

crates/eficore/src/lib.rs

@@ -29,6 +29,8 @@ pub mod strings;
 
 /// Implements support for the bootloader interface specification.
 pub mod bootloader_interface;
+/// Acquire arguments from UEFI environment.
+pub mod env;
 /// Support code for the EFI framebuffer.
 pub mod framebuffer;
 /// Support code for the media loader protocol.